The relegation places are supposed to be contested by the three promoted clubs and a sprinkling of weaker and poorer sides whose hold on their Premier League place is unsteady. That, at least, is the theory.
What can happen is that more established clubs, with supposedly better players and higher aspirations, can be dragged into the battle at the bottom. As it stands, Everton and West Ham are both in the lowest third of the table, though few tipped either for the drop. But that has not always been enough to save clubs in an unexpected relegation fight.
BLACKBURN ROVERS (1998-99)
Pedigree: Champions in 1995, Blackburn had finished sixth under Roy Hodgson in 1998. With benefactor Jack Walker still alive, they were among the big spenders of the era, forking out around £40 million in transfer fees alone in 12 months.
Players: Survivors of their title-winning team, such as Chris Sutton, Tim Sherwood, Tim Flowers and Jason Wilcox, talented youngsters like Damien Duff and David Dunn, Liverpool players of past and future in Jason McAteer and Stephane Henchoz plus numerous expensive arrivals (Kevin Davies, Matt Jansen, Lee Carsley, Ashley Ward, Nathan Blake and Keith Gillespie).
In trouble because: Too many of the signings failed. Davies became the club's record buy, but only scored one league goal. Christian Dailly, to widespread bemusement, was the fourth most expensive defender in the world at the time but proved unable to replace Colin Hendry, a Rovers legend. With Graeme Le Saux returning to Chelsea and Sherwood leaving mid-season, the title winners were disbanded. Hodgson was sacked in November; a glimpse at the rest of his record suggests he would have overseen survival.
Went down because: Choosing Brian Kidd to replace Hodgson, though a widely acclaimed choice at the time, backfired. A side with a surfeit of experience and a squad with numerous options nonetheless failed under pressure, not winning any of their final eight games. Injuries, particularly to Sutton, did not help, but despite possessing seven costly front-line forwards, none managed more than five goals in the campaign.
COVENTRY CITY (2000-01)
Pedigree: Since promotion in 1967, Coventry had been in the top flight for longer than Manchester United, Tottenham, Chelsea, Aston Villa, Leeds and Newcastle.
Players: Several emerging talents, in Craig Bellamy, Chris Kirkland and David Thompson, plus the sort of solid citizens Gordon Strachan often values, but with the flair of an African Footballer of the Year, in Mustapha Hadji. John Hartson also joined for the relegation run-in.
In trouble because: After losing George Boateng and Darren Huckerby the previous season, Gary McAllister and Robbie Keane departed in the summer of 2000. Coventry struggled to replace all: Bellamy, bought to fill in for Keane, spent much of the campaign on the left wing. Two of the experienced players, Carlton Palmer and Colin Hendry, fell out of favour and left during the season.
Went down because: Their home form deserted them. Just four wins and a mere 14 goals at Highfield Road were not enough. After a good start, they fell away and they did not win a league game in September, November, January or February. Hartson arrived too late to lift them to safety.
WEST HAM UNITED (2002-03)
Pedigree: Came seventh in 2002, 17 points above the relegation zone. Were playing in the Premier League for a 10th consecutive season and produced a crop of talented young players that was arguably unrivalled in England at the time.
Players: Joe Cole, Michael Carrick, Jermain Defoe and Glen Johnson among the homegrown contingent, a genuine West Ham great in Paolo di Canio and an England goalkeeper in David James. For the end of the season, they had Lee Bowyer and Les Ferdinand as well.
In trouble because: They didn't win any of their first 12 home league games of the campaign. A defence that became the subject of mockery didn't help either; Gary Breen, allegedly wanted by Barcelona, joined West Ham but formed a terrible quartet of centre backs with Tomas Repka, Ian Pearce and Christian Dailly. The mercurial Di Canio played in less than half their league games.
Went down because: They lost 1-0 at Bolton in April and Wanderers stayed up, two points ahead of West Ham. An end-of-season revival that brought ten points from the last four games came too late as they went down, despite taking 42 points. Manager Glenn Roeder struggled to deal with some of the bigger personalities in his dressing room.
LEEDS UNITED (2003-04)
Pedigree: Champions League semi-finalists in 2001 and in the last four of the Uefa Cup 12 months before, they had finished in the top five in five of the previous six seasons. Heavy expenditure gave them a squad that appeared to have genuine aspirations to challenge Manchester United for domestic dominance.
Players: Three generations of fine Leeds players, from David Batty and Lucas Radebe via their golden generation of Paul Robinson, Alan Smith and Ian Harte to the teenage talents of Scott Carson, Aaron Lennon and James Milner. Add in some England internationals (Seth Johnson and Nicky Barmby), a World Cup winner (albeit Roque Junior) and the class of Mark Viduka and they surely shouldn't have gone down.
In trouble because: Peter Ridsdale struggled with his arithmetic? Lee Bowyer and Jonathan Woodgate were involved in a court case and David O'Leary's book about that period was entitled 'Leeds United On Trial'? The reasons are many and well documented. Selling Harry Kewell, Rio Ferdinand, Robbie Fowler, Robbie Keane and Woodgate in the space of two years was financially necessary, but weakened the squad.
Went down because: Started the season terribly (two wins in 13 games) and didn't improve enough. Giving Peter Reid, the previous season's firefighter, the job on a permanent basis proved a mistake, with his loan signings, Jermaine Pennant apart, underachieving. Eddie Gray, the caretaker manager, briefly rallied a club that was falling apart, but not to sufficient effect. Conceding 48 goals in 19 away games showed that, minus Ferdinand, the defence fell apart. That Viduka got sent off twice in the final two months of the season and was banned for vital games meant a potential match-winner proved a liability.
Pedigree: Playing top-flight football for a 27th consecutive season, they had reached the FA Cup final and finished eighth in 2003. Never seemed to go down, no matter how many people expected them to.
Players: Three England international strikers, of past and future, in James Beattie, Kevin Phillips and Peter Crouch, an outstanding goalkeeper in Antti Niemi and the nucleus of the FA Cup final side.
In trouble because: Gordon Strachan left early in 2004 and Rupert Lowe's attempts to replace him were farcical; Paul Sturrock and Steve Wigley were out of their depth, Harry Redknapp was at the wrong club and the long-term plan to bring in Clive Woodward was ludicrous. Opted for quantity rather than quality in their signings, with only Crouch actually benefiting an oversized squad.
Went down because: Took long to even realise they were in a relegation battle, squandering winnable home games, especially in the first half of the season. Their established goalscorer (Beattie) left in January, their finest defender (Michael Svensson) missed the entire campaign with injury and the midfield mainstay of previous campaigns (Matt Oakley) barely featured. Key players such as Niemi and Claus Lundekvam lost form while Crouch, when he appeared a potential saviour, got a red card in the penultimate game at Crystal Palace.
NEWCASTLE UNITED (2008-09)
Pedigree: Twice runners-up in the Premier League and with three top-five finishes in the previous seven seasons, they were in the top flight for a 16th consecutive campaign.
Players: Two expensive Argentine internationals (Fabricio Coloccini and Jonas Gutierrez) joined an expensive, if badly compiled, squad that included Michael Owen, Mark Viduka, Obafemi Martins, Alan Smith, Nicky Butt and Damien Duff.
In trouble because: Kevin Keegan left early in the season after disputes with owner Mike Ashley and executive director Dennis Wise. Ashley put the club up for sale without finding a buyer while four managers - Keegan, Joe Kinnear, Chris Hughton and Alan Shearer - were in charge for varying parts of the season.
Went down because: Kinnear sold the best goalkeeper in the league, Shay Given, in January. A costly attack struggled for goals, with just 40 managed in 38 games. Coloccini continued Newcastle's unfortunate reputation for poor defending while a team of considerable ability only won one of their last 13 games and were relegated without a fight on the final day at Aston Villa.